The present invention relates to a card-type thin electronic device approximately 0.8 mm thick. It is generally comparable to the standard credit-card size, and more particularly, with the package arrangement made up of upper and lower panels and a frame for internally mounting a variety of electronic components to make up a complete thin-type electronic device.
As shown in FIG. 3 of the appended drawings, the conventional package arrangement of a thin electronic device is composed of a pair of stainless-steel upper and lower panels 1 and 2. These are bonded with a polyamid bonding agent, for example, to a flange 4 projecting out from the internal surface of a frame 3, which makes up the lateral walls.
The thin constitution of such electronic devices requires a high bending strength. To achieve this, the upper and lower panels 1 and 2 are made of material with an adequate ability to withstand tensile and compressive forces. The panels 1 and 2 are bonded to a frame 3 using a bonding agent with adequate elasticity. These two measures ensure the necessary bending strength. Conventionally, in the light of operating efficiency, a sheet-like thermoplastic bonding agent 5 is used. However, there is a limited availability of sheet-like thermoplastic bonding agents with adequate elasticity. Thus depending on the type of materials used for the upper and lower panels 1 and 2 and the frame 3 to be bonded together, satisfactory bonding often cannot be achieved. Consequently, the postions of these panels 1 and 2 occasionally deviate when a bending force is applied. Furthermore, to improve the bond, a primer conventionally is applied to the surfaces of the panels 1 and 2 to be bonded. Factory employees usually perform this primer-coating operation manually, thus, the complicated production processes eventually result in higher costs. In addition, unless a proper amount of the bonding agent is applied, the agent itself may leak outside of the assembled product.